The health
investigation levels (HILs) for 2,4,5-T and 2,4-D are derived in Schedule B7,
Appendix A4 of the NEPM with full details of the toxicological review. You can also see them in
the summary calculation table in Appendix C. The units have always been
reported as mg/kg for both these substances.

The health screening
levels (HSLs) in the NEPM trigger the duty to notify the EPA of site
contamination under section 60 of the Contaminated Land Management Act 1997 if levels of selected petroleum
hydrocarbons meet or exceed the HSLs along with the other criteria required
under section 60(3).

The NSW EPA
considers it is appropriate to apply HSL land-use category D
(commercial/industrial) to assess potential vapour intrusion for multi-storey
buildings with residential uses at ground level and where a car park exists in
a basement, subject to the HSL application restrictions detailed
in the NEPM and in Technical Report No. 10 - Health screening levels
for petroleum hydrocarbons in soil and groundwaterpublished by the CRC for Contamination Assessment and Remediation of the
Environment (E Friebel and P Nadebaum 2011).

The ecological Investigation levels (EILs) and ecological
screening levels (ESLs) are still ‘single point’ criteria, However, although not explicitly stated, the
information provided in Schedule B1 intends to allow for statistics to be
applied to both human health and ecological criteria. The statistics are
calculated for a relevant ‘area’ based on the conceptual site model, taking into
account the receptors present.

Further guidance about
ecological assessment is provided in Section 3.4.2 of Schedule B1.

The correct ESL is
1.4 mg/kg for BaP in both coarse and fine soil. There was an error in the
review paper, which has been corrected.

The correct ESL for
xylene is in Table 1B(6) of Schedule
B1. The author’s explanatory papers are in the NEPM toolbox.

No. While the NEPM
only provides EILs for a limited number of analytes, it also provides the
methodology to develop EILs for other analytes, such as those for which phytoxicity-based investigation levels
have been included in the site auditor guidelines.

Fill materials

uncontaminated natural materials from a known local source such as clay and
sand used for levelling or landscaping purposes (‘clean fill’), and

heterogeneous fill of unknown origin

While an ambient
background concentration (ABC) could be calculated through sampling and
analysis for clean fill of known origin and date of emplacement, it is not
appropriate to calculate or derive an ABC for other types of fill.

Fresh and aged lead

The EIL spreadsheet
in the NEPM toolbox presents the added contaminant limits (ACLs) for fresh and aged lead as
‘generic EILs’ without the option to estimate the ambient background
concentration. This is a flaw in the spreadsheet. The lead EIL can be
calculated as per the procedure in Schedule B1, Section 2.5.10 (EIL = ABC +
ACL) or refer to Schedule B5c which contains several sample calculations for
lead.

Note that there is also
an error in Schedule B5c, Section 8.7.3.3. The worked Example 1 (SQG based on
LOEC and EC30) shows the ABC for lead as 150 mg/kg for an old suburb with low
traffic volume in South Australia. This should read 30 mg/kg and is displayed
correctly as such in Table 67 on page 76.

Added contaminated limit for copper

Organic carbon data
is not needed to determine the ACL for copper. only pH and cation exchange
capacity (CEC) are required. Refer to Appendix F in Schedule B5c for a more
detailed explanation.

The groundwater investigation levels (GILs) in the NEPM refer to Guidelines for managing risks in
recreational waters 2008. There
is currently no intention to approve these guidelines under section 105 of the CLM Act. However, it is expected that site
auditors and consultants will use the most recent version of guidelines in
their contaminated sites work.

Toluene in groundwater

Does the criterion
for toluene of 300 ug/L in the Guidelines for assessing service station
sites (EPA 1994) still apply?

The NEPM does not
present a GIL for toluene for fresh and marine waters, but it does include a
GIL for drinking water. The NEPM notes that additional GILs applicable to
industrial, agricultural and recreational uses are provided in other documents
as referenced in Table 5 of Schedule B1. The NEPM does not present a
groundwater HSL for vapour intrusion because it is not limiting.

The Australian
water quality guidelines 2000 include low reliability trigger values for
toluene. These guidelines are approved by the EPA under section 105 of the CLM
Act. You can consider whether they are appropriate for application to a site,
for example, is 95% protection level appropriate?).

The management
limits for petroleum hydrocarbons are applied after considering relevant ESLs
and HSLs.

Guidelines for
the NSW site auditor scheme (3rd edition) state:‘for petroleum hydrocarbon compounds, the site auditor should also consider the management limits referred to in s.2.9 and Table 1B(7) of Schedule B1 of the NEPM. The management limits should be considered after consideration of the health screening levels and ecological screening levels for petroleum hydrocarbons.’

In general, the
presence of asbestos does not mean a site must notified to the EPA under section 60 the CLM Act. Sites may be regulated under the CLM Act
where the EPA determines that there is ‘significant contamination’ of land,
such as where the scale and nature of the contamination is giving rise to
actual or potential harm to human health or the environment. This could occur
where there are elevated levels of asbestos fibres in air and the responsible
party is not addressing the source of the risk.

The missing table
of recommendations for PCBs was inadvertently omitted from the final version of
the NEPM but has been included in the errata list that is now available.

Referencing

An appropriate
reference to the amended NEPM would be National Environment Protection
(Assessment of Site Contamination) Measure 1999 (April 2013), NEPC 2013,
Canberra.

An example of how
to distinguish between the original and amended NEPM in a report could be to
reference the amended measure as ‘National Environment Protection
(Assessment of Site Contamination) Measure 1999 (April 2013)’ and the original as ‘National Environment
Protection (Assessment of Site Contamination) Measure 1999 (1999)’.